"I followed the Shadow's plan," she whispered. "It showed me how to snatch the cathode gun from the robot guard who brought me food. How to escape through the long black corridors of Malgarth's temple. How to reach the geodesic sled that was waiting for one of his silver-winged robot commanders. There was pursuit. But the ship was very swift. And I _had_ to reach you, Kel!" The Earthman then bent over her, tensely. "You did." And his voice snapped with the question: "Can you guide us back to Mystoon, Verel? Do you know the way?" Faintly, she nodded again. "It's a long, strange way, Kel. But I can try. For we must reach the Stone before it is destroyed." "Or," Kel Aran put in grimly, "before we are!" Then I ventured to ask an anxious question. "If this Stone has the power to destroy Malgarth," I asked, "why doesn't it destroy him?" "If it were as simple as that--" The girl's somber, curious eyes came to me again. "The ages must have fogged your memory, Barihorn. The Stone has the secret of Malgarth's doom, yes. But it has no power to act alone. The Shadow can only guide its human helpers. That is why there were Custodian and Warders." * * * * * Her head shook gravely. "No, Barihorn, the Stone can never strike at Malgarth, unless we arrive to aid it." Red stars followed us again--the repulsors of pursuing robot ships. But Kel Aran, singing a gay new song of the return of Barihorn and the vengeance of the old Dondara Stone, drove our tiny ship through a dark asteroid cluster. The ponderous cruisers of the fleet were delayed in finding safe passage through those black hurtling islands of space. We gained a little margin of time. And then, with Verel for a guide, Jeron turned the _Barihorn_ toward the secret world of Malgarth's lair. It was toward the great Horse's Head nebula in Orion that she directed us, that strange ink-black silhouette against the stars that had so puzzled the astronomers of my own day. Twice again we evaded the red stars that pursued. And at last the girl guided us into the dark peril of the stellar cloud. Vast beyond comprehension, it was a lightless cosmic desert of drifting dust and hurtling rocks and plunging planetary bodies. On all the space charts it was marked, _dangerous, impenetrable_; all shipping was warned to keep two light years clear of its dark fringes. But Malgarth, it seemed, had found a safe path through its perils, half a million years ago. With Verel's aid, we found that path, and followed it. And all the stars were lost in that cloud of universal darkness--even the crimson stars that had pressed so close behind us. "I think we have left them," said Verel Erin. "For even the most of the robots do not know the dark way we go.--But there are others enough, waiting for us. Mystoon is guarded well."